The invention springs out of a need in the industry for providing a valve sealing device that is multifunctional and simple to produce, and which is safer and more versatile than known valve sealing devices for drinking receptacles. This need is particularly aimed at providing a sealing device exhibiting a safer sealing function when the valve is in the storage mode.
There is also a need for providing a sealing device that prevents unintentional opening of the valve for undesirable invasion of an aseptic solution, which otherwise is used for bactericidal treatment of the valve and associated components. In this connection, and for hygienic reasons, the downstream side of the valve may be sealingly connected to, and is enclosed by, a protective cover or similar. During the aseptic treatment process, the valve and the protective cover is normally immersed into a heated aseptic solution containing a bactericide. An air cushion, which is located between the protective cover and the valve, will thus be heated so as to increase the pressure in the air cushion. If the sealing device of the valve is inadequately gas-tight, the increase in air pressure will ensure that air leaks out of the air cushion via the valve, which reduces the amount of air in the air cushion. Subsequently, when the aseptic treatment is ended and the reduced amount of air in the air cushion is cooled, an underpressure will form in the air cushion. Insofar as the sealing device of the valve is inadequately gas-tight, this underpressure may cause air to be sucked unintentionally back and into the protective cover via the valve. This air flow through the valve may then entrain liquid residues from the aseptic solution and onwards into the protective cover where the liquid residues may be deposited as droplets and/or solid deposits on the cover and the valve. Such droplets and/or solid deposits are visually unappealing and may inflict foul taste in the beverage during consumption thereof. Such an effect is therefore undesirable.
Accordingly, there is a need for providing a sealing device that functions satisfactorily under different conditions to which the valve is exposed during its operating lifetime.